Three-dimensional integrated circuits (3DIC), enable increased circuit density, which is well suited to the requirements of modern electronic devices. In many cases, through-silicon vias (TSV) are being used to stack the dies together and to connect the dies to package substrates.
A through-silicon-via, or TSV, provides electrical continuity between the top and bottom surfaces of a semiconductor chip. A TSV is fabricated by deep etching into the silicon wafer, or substrate, which comprises the semiconductor chip, and filling the resulting hole with a liner and a metal filling. The silicon substrate is then ground, or thinned, from the backside until the metal filling is exposed, and backside metal (BSM) is disposed on the thinned backside surface for electrical contact. TSVs are an important part of 3D integrated circuits. It is therefore desirable to have improved structures and methods for testing 3D integrated circuits that utilize TSVs.